Regarding the Weather
My heart goes out to all those affected
by the recent flooding. Whether you are dealing with a leaky roof,
water in your basement, or more trouble than that, my thoughts and
prayers go out to you.
Hopefully you have your home sprinkler system turned off for now. Let
the plants be your guide as to when to begin watering again. However,
plants can be tricky: they may look droopy both when they are dry and
when they are over-watered. The only thing a droopy plant is telling
you for sure is that it requires attention. Check the soil moisture
with your fingers to determine the solution. Also, container gardens
will dry out much more quickly than plants in the ground. Clear skies
are forecast for the next few days so you may need to water your potted
Insecticide: Organic Options
Last month, I commented on the
importance of proper diagnosis of a pest problem before choosing a
treatment option. I'd like to reiterate that and
that once you have a diagnosis, CAREFULLY READ THE LABEL before
applying any kind of insecticide. Improper dilution or inappropriate
application can be very, very harmful to you and the environment around
This month I'll give you some
information about botanical/natural or organic pesticides. But first, I
want to stress that just because an insecticide is labeled "organic" or
"natural" DOES NOT MEAN IT'S PERFECTLY SAFE or
harmless to the environment. Even natural insecticides should not be
applied willy-nilly all over the garden. Please take care and use good
judgment for all types of pesticides.
I keep a newsletter archive
on my website which may help you identify the pest. Additional
resources are listed at the bottom of this page and staff members at
our local nurseries are very helpful in identifying pest problems and knowledgeable regarding insecticides.
Here I will briefly discuss the three most common types of organic insecticides.
If you have concerns or questions about your container gardens or irrigation system, please contact me right away.
Botanical. In this category is any insecticide which is primarily made from plants. Examples include Pyrethrum (from the Chrysanthemum cinnerariaefolium flower) which is a good broad-spectrum insecticide. Neem Oil (from the tropical Azadirachta
tree) is effective against a number of pests including aphids,
caterpillars and beetles. Some botanical solutions, such as garlic or
hot pepper oil, are really repellents - the pests will leave the plant
to which it is applied but are not killed. To make the point that
organic/botanical insecticides are still potentially dangerous,
Nicotine (from tobacco plants) and Rotenone (from the Derris elliptica plant) are two botanicals which are banned by the EPA because of their toxicity.
Bacteria. There are several types of bacteria that work on pest insects. The most common is Bacillus thuringiensis,
commonly referred to as Bt. Bt is target-specific which means it won't
kill anything but the one pest for which it's intended. Bt is
frequently used against mosquito larvae but there are also Bt strains
available which are effective against caterpillars, flies and beetles.
Other commonly available and effective bacteria strains are Beauvaria bassiana and Bacillus popilliae.
Non-carbon based. This
term means anything that was not ever living. The category includes
mineral derived insecticides such as sodium fluoaluminate and boric
acid which are frequently used in traps - like those little black ant
traps. Diatomaceous earth is effective against crawling insects,
especially slugs. Soaps are included in this category and can be
effective against many soft-bodied pests but can cause the plant's
leaves to burn. As always, read the label and follow the application
Also, if you're considering doing some landscaping work, please call me (970-988-3808) to help you with your landscape design.
This is the final installment for this year's newsletter series "Insects: the Good, the Bad and the Ugly."
The Good: Syrphid Flies
Resembling small wasps with a yellow or
white striped abdomen, these flies are pollinators and predators. They
hover like hummingbirds thus earning the common name Hover Fly. Unable
to sting, they are harmless to humans. The larvae looks like a small
green caterpillar which can be as small as 1/32" or up to 1/2"
depending on development and species. The larvae consume soft-bodies
pests such as aphids (their favorite), mealybugs and small
caterpillars. Hover Fly females will only lay eggs on pest-infested
plants and the number of eggs laid is dependent on the population of
pests. Attract Syrphid Flies to your garden with blooming plants.
The Bad: Grasshoppers
Grasshoppers are green or brown,
hatching in March through June. The nymphs look like adults but are
smaller and feed voraciously. Mature grasshoppers in the heat of summer
are much less vulnerable to pesticides. When cleaning up in the fall
and winter, watch for and destroy egg clusters, which can be clusters
of 75 or more cream or yellow rice-shaped eggs. Population of
grasshoppers varies from year to year and if the current year had a
high population, it doesn’t necessarily mean the following year will.
The Ugly: Earwigs
Despite folk tales, earwigs are harmless
to humans and have no interest in the ears of livestock. Dark brown and
about ½" to ¾" long, the large rear pincers make them especially ugly.
Decomposers, they feed on dead and dying debris and have also been
known to eat some pest insects such as aphids and mites. Leaves
of plants eaten by earwigs are chewed around the margins and have
ragged holes. Earwigs also like to eat maturing fruits and vegetables
by boring holes into the flesh. A tidy garden, free of decaying leaves
or other debris, helps to deter earwigs. If they are especially
bothersome in your vegetable garden, you can try using a beer trap or a
commercially available pesticide dust.
If you're really interested in bugs, here are a few good resources:
"Insect." Wikipedia. Wikipedia Foundation, 27 Apr. 2013. Web. 29 Apr. 2013.
Walliser, Jessica. Good Bug, Bad Bug:
Who's Who, What They Do, and How to Manage Them Organically: All You
Need to Know about the Insects in Your Garden. Pittsburgh, PA: St. Lynn's, 2008. Print.
Sunset Western Garden Book. Menlo Park, CA: Lane, 1988. Print.
Leatherman, David, and Whitney Cranshaw. Insects and Diseases of Woody Plants of the Central Rockies. [Fort Collins, Colo.]: Colorado State University Cooperative Extension, 2000. Print.